I have other megas but I don't use them as often. Although Despite my M-Seadramon having the highest lvl and highest DP it is the weakest of my main 3 and I don't know why. If anyone can tell me how to take steps to fixing that, let me know please.

I plan to DNA M-seadramon with Machinedramon to get skullgreymon. That to machinedramon and hopefully based off the fact that its a Virus digimon it will be really strong, but after it makes at 45 or something I will DNA it with Airdramon and train a Veemon to Imperialdramon which should be an epic thing maxing in the 50's

Although Despite my M-Seadramon having the highest lvl and highest DP it is the weakest of my main 3 and I don't know why. If anyone can tell me how to take steps to fixing that, let me know please.

Depends on how you got it in the first place. If you used powerful Digimon, it would be powerful. If you used Digimon with low stats, of course it will be weak. I have an example too: while this Raidramon I have was Phoenixmon, it maxed out at el 45 and was the strongest one, but had barely more HP and MP than this Seraphimon I have. So it depends on what you use to make your Digimon.